How to Wash Period Underwear

So your daughter has her first pair of period undies and now you're both staring at them wondering what comes next. Fair enough. Nobody really tells you this part. The good news is that learning how to wash period underwear is genuinely straightforward once you know the steps. And once you've got the routine down, it just becomes part of life. If you're still getting your head around them, here's how period undies actually work.

At Fanzy Pantz, we hear from mums all the time who want to make sure they're looking after the undies properly so they last. Because when your daughter is sorted with period underwear that actually works, the last thing you want is to accidentally wreck them in the wash.

Step One: Rinse Them Out First

This is the most important part. Before anything goes in the washing machine, give the underwear a cold water rinse straight after wearing. Just hold them under the tap and rinse until the water runs clear. Cold water only here. Hot water will set the stain and break down the absorbent layers faster.

This step takes maybe 30 seconds and it makes a huge difference. If your daughter is coming home from school or a sleepover, she can just rinse them in the sink before dropping them in the laundry. Simple habit, big payoff.

Step Two: Machine Wash on a Gentle Cycle

Once rinsed, pop them in the washing machine with your regular load. Use a gentle or delicate cycle with cold or warm water. Nothing above 40 degrees. Hot wash cycles are the enemy of period underwear because the heat damages the absorbent core over time.

Use a mild detergent. Skip the fabric softener completely. It sounds harmless but fabric softener coats the fibres and actually reduces the absorbency. That means leaks. And nobody wants that, especially not mid-sport or at a school sleepover.

If you want to be extra careful, a mesh laundry bag is a great idea. It protects the underwear from getting tangled or stretched in the machine. Every Fanzy Pantz kit comes with one, along with the other bits she'll actually use. Here's what's inside every Fanzy Pantz kit.

Step Three: Air Dry Every Time

This is the other non-negotiable. Always air dry period underwear. No tumble dryer. The heat will break down the layers that do the hard work, and over time your daughter will end up with undies that just don't hold up the way they should.

Hang them somewhere with good airflow and let them dry fully before storing. In summer that takes no time at all. In winter you might need to plan a little ahead. A drying rack near a window works perfectly.

What About Stains?

Sometimes a cold rinse isn't quite enough and there's still a bit of staining. That's completely normal. A little bit of staining doesn't mean the undies aren't clean. But if it bothers you, try soaking them in cold water with a small amount of mild detergent for 15 to 30 minutes before washing.

You can also use a gentle stain remover, just check it's safe for delicate fabrics first. Avoid bleach. Bleach will damage the material and is way too harsh for something worn against your daughter's skin.

How Often Should You Wash Them?

After every single wear. That's it. Period underwear is designed to be washed and reused, but it needs a proper wash each time to stay hygienic and keep performing well. Don't let them sit in a pile for days. Rinse and wash as soon as you can after wearing.

This is actually a good habit to teach your daughter from the start. It becomes part of her routine. Rinse, wash, dry. Done.

Quick Recap: The Dos and Don'ts

Do: rinse in cold water straight away. Wash on a gentle cycle. Use mild detergent. Air dry fully.

Don't: use hot water. Use fabric softener. Put them in the dryer. Use bleach.

How Long Will They Last?

With the right care, a good pair of period underwear can last for years. That's genuinely good value, especially when you're buying multiple pairs to get your daughter through a full cycle without running out. The Tween Period Underwear 5-Pack ($99) is the easy way to get five pairs at once. Look after them properly and they'll look after her.

Knowing how to wash period underwear properly is one of those small things that makes a big difference to how well they work long term. And when your daughter is relying on them at school, sport or a sleepover, you want them performing at their best every single time.

Teaching Your Daughter the Routine

One of the nicest things about period underwear is how manageable it makes everything. Once your daughter knows the wash routine, she can handle it herself. That's a big deal for confidence. She's not caught out, she's not stressed, she's just sorted. If you're choosing pairs for her, here's our guide to choosing period underwear for teens.

Start simple. Show her once. Let her do it herself the next time. It really does become second nature quickly.

If you're still pulling everything together for her first period, our First Period Tween Kit ($49) has everything in one place. Period underwear, liners, a little bag for her school bag, and a guide that makes the whole conversation easier. For the premium version with accessories and the book, take a look at the Ultimate First Period Kit ($85). It's designed for real life, for real girls, and for mums who want their daughter sorted before she needs it. Have a look and see if it's the right fit for your family.